As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOT REPORTED ENGINE OIL ON NR 1 COWL WHEN COWL WAS REMOVED IT WAS NOTICED THAT THERE WAS OIL ON TOP OF THE NR 6 CYL. HOLD DOWN STUDS. AFTER THE ENGINE WAS CLEANED IT WAS GROUND RUN AND THE OIL APEARED TO BE COMING FROM AROUND THE STUD BUT AFT ER FURTHER INSPECTION AND PAINT REMOVAL THERE WAS A HAIRLINE CRACK APPROX. 1.5 INCHES IN LENGTH.THE ENGINE WAS REMOVED AND A NEW CASE WAS INSTALLED.